1. Field of the Invention
This patent relates to work piece holding devices used to hold work pieces for machining or other purposes. Work pieces that are machined must be held or clamped to prevent their movement caused by forces acting against them.
It is generally desirable to have a high degree of rigidity and accurate work piece location so that the surfaces which are treated (usually by cutting) on the work piece is well within acceptable tolerance.
2. Description of Prior Art
Existing work piece holding devices range from a simple vice designed to hold one work piece, wedge lock side clamping of single or multiple work pieces located on a single base and dedicated fixtures constructed for a specific work piece.
Vertical hold down clamps (called swing down clamps) are available for clamping work pieces against their top surface. They swing out of the way when unclamped to permit removal of the work piece.
Exiting wedge clamps are generally fixed to a base with serrations or keys that are difficult to clean and difficult to determine the exact work piece location.
They generally require manual clamping.
Swing down clamps are generally located on dedicated fixtures. They are usually powered by hydraulic systems. Their hydraulic lines tend to collect chips and are difficult to clean.
Power clamping is usually accomplished using hydraulic systems. This complicates the systems need for decoupling the hydraulic lines when the clamping system is removed from a machine tool for off machine work piece handling.